we have a sniff test in our state, and the door tag said its a 8600 GVW# and i do care what front axle cuz it may need some minor work on the front locking hubs seeing as they make a little noise when taken out of 4wd but other then that i know its a dana ttb so right now thats good enough.

 

Measure the hubs. A Dana 50 TTB will have the same hubs, knuckle out, as a Dana 60. They should measure 4", 3.25" or 3.5" is Dana 44.
I'd check the requirements for heavier duty vehicles. At a minimum it should have looser requirements as it would never meet the same emissions standards as a catalyst truck, even off the showroom floor.

 

Having to pass a sniff test for an 8600# GVWR vehicle might not be too bad. The 351 HO had quite a bit of hoses running hither and yon, but it wasn't terribly complicated and didn't have expensive parts. No cat, no ECU, etc. Worst case would be getting the AIR pumps working, replace some vacuum lines that may have cracks, and maybe rebuild the carb and replace the EGR valve.

I think I would find an AIR pump at a salvage that will spin, or PM me as I have one, put it on and see if it passes. If not they'll tell you what didn't and you can go from there.

 

I just ran across these notes of mine and thought you might be interested:


According to Thumper's site:
E7TE flows 156/108 @ .500" with 1.74/1.46" valves
GT40 flows 185/129 @ .500" with 1.85/1.54 valves
GT40P flows 196/139 @ .500 with 1.85/1.46 valves

CASTING CC. VALVES. COMMENTS
D9AE-AA 68.75 1.78/1.46. 79-84 302
E5AE-CA 68.5. 1.78/1.46. 85 302
E6AE-AA 63.5. 1.78/1.46. 86 302
E5TE-PA 63.5. 1.78/1.46. 87-93 302
E7AE-AA 63.5. 1.78/1.46
E7TE-PA 62. 1.78/1.46
F3ZE-AA 61.5. 1.84/1.54. 93 Cobra GT40
F4ZE-AA 61.5. 1.84/1.54. 94-95 Cobra GT40
F1ZE-AA 61.5. 1.84/1.54. 96-97 Explorer GT40 (or F1ZZ?)
F77E-AA 59.5. 1.84/1.46. 97-00 Explorer GT40P
E5AE-CA 69.5. 1.78/1.46. 85-86 351W
E7TE-PA 63.5. 1.78/1.46. 87-95 351W

I don't remember which magazine that came from, but I do know there are some discrepancies, like the E7TE-PA's being listed twice with different combustion chamber sizes. But, the reason you may want to look at it is the combustion chamber size of the GT40P's is small enough you may have problems with pinging or detonation.

 

I wanted to clear this statement up. HD trucks came standard with the dana hd 44ttb up front(even diesels and 460's). Only the extended cab HD f250 trucks and possibly special order regular cab f250's came with the dana 50 ttb.

 

Ah, very good info! Just when you think you've about got it figured out. Thanks Franklin! I wasn't aware of that detail. Makes sense seeing as mine is a SC.

 

what is the stock compression ratio for an 86 351w HO?

 

Jordan,
I believe the compression ratio was listed as 8.5:1. However, I'm not sure they really were as the combustion chambers were very large in those heads and the deck height for the pistons was well down in the bore.

 

i see, i was wondering cuz the later 351w with gt40p heads they are getting about 9.1:1 compression so i wanted to see how much it might net me, but if your not sure on that number i'll just run a compression test and see what comes up on that truck

 

Don't know what the '86 HO would have had for heads, but the '85 I parted out had large combustion chamber heads ~ 69 cc's. You'll have a lot of compression with the GT40P's.